Humidifiers are used, for example, to introduce a liquid, such as water, to a gaseous medium, such as air, in an air conditioning system. Mist generators or mist sources, such as steam producing heaters, atomizers, nebulizers and ultrasonic vibrators have been used to present liquid in the form of droplets to a passing flow of gas. Many prior systems orient a plurality of mist generators, such as nozzles in rows that are positioned transverse to the air flow. These systems are thus limited by the lateral space parameters of the surrounding duct work or passage.
The prior systems are also limited in the range of air speeds that can be accommodated. Because complete evaporation of the water droplets is a function of the size and quantity of the droplets, some droplets do not completely evaporate before encountering a curve in the duct or passageway in which the gas is flowing. Unevaporated water droplets can collect on the duct work at the curves, causing dripping onto associated ceilings or rooms. This phenomenon is sometimes referred to as raining.
It has been necessary to limit the air speed in humidified systems to avoid or minimize raining. In fact, prior systems have been limited to air speeds of less than 800 feet per minute to allow sufficient time for evaporation of acquired liquid before the flow passes a curve or other transition in the passage.